Global collective action is the key to solving climate change

Ian Katz says "it is hard to see where the political leadership for a global [climate] deal will come from" (The case for climate action must be remade from the ground upwards, 9 February). With climate science under siege and climate politics in disarray he's absolutely right that "anyone who cares about this issue must fight to keep it alive". I believe that pressure will need to come from a new and much broader global grassroots movement. It will need cross-party political support and must engage the business community.

With Copenhagen behind us, it's time for a new discourse, one which acknowledges the majority view on climate science, accepts uncertainties, and encourages debate among scientists over their observations of the world. A debate framed in the language of risk and uncertainty in which economics and societal values will play a central role.

We have to recognise that a global climate deal will be unlike any other previous international agreement. What we are seeking is a radical transformation of the global economy. If we view it as just another agreement that can be achieved with a bit of lobbying and mass mobilisation it won't work. The world generally needs to be shown that the transition to a low-carbon economy can really happen. And to achieve that requires real leadership from politicians and an unprecedented engagement with the public.

Katz suggests that the consequences (and causes) of the Copenhagen failings may take some time to divine. But it's clear that the policies presented by governments in Copenhagen failed to transcend short-term national interests for the greater global good.

In a carbon-constrained world it is going to be necessary to decouple human development from climate pollution. At Copenhagen world leaders could have signed an agreement that would have meant, in short, a radical transformation in the way we provide transport, energy, food, shelter, and other basic needs for all of the world's population. The opponents of action to tackle climate change talk about the costs. If we are to engage the public in the transition to a new economy we need to talk about the benefits, which will always outweigh the costs because of the catastrophic nature of climate change.

Katz says "there is a strong case for more radical reforms", but adds: "Those who want action on climate change will meanwhile have to accept a more incremental approach." Maybe. But we cannot accept a "climate apartheid", where only the rich can buy their way out of the problem. Gandhi taught us that peaceful movements can win, but you need a common cause and mass mobilisation. Climate change is a global public "bad". To solve it requires global collective action.

Perhaps a more global conscience is a distant dream. But dream we must. We have no alternative but to build a global grassroots movement, move politicians forward, and force large corporations and banks to change direction. Civil society needs to sharpen its teeth if it is to win the battle to save the climate.

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